Optical compensation film, polarizing plate, and liquid crystal display device

Abstract

Disclosed is an optical compensation film comprising an optically-anisotropic layer and at least one optically-isotropic layer adjacent to the optically-anisotropic layer and having a refractive index that differs from the mean refractive index of the optically-anisotropic layer.

1. An optical compensation film comprising:
 an optically-anisotropic layer and 
 at least one optically-isotropic layer adjacent to the optically-anisotropic layer and having a refractive index that differs from the mean refractive index of the optically-anisotropic layer. 
 
     
     
       2. The optical compensation film of  claim 1 , wherein the refractive index of the optically-isotropic layer is smaller than the mean refractive index of the optically-anisotropic layer. 
     
     
       3. The optical compensation film of  claim 1 , wherein the refractive index of the optically-isotropic layer is larger than the mean refractive index of the optically-anisotropic layer. 
     
     
       4. The optical compensation film of  claim 1 , wherein the difference between the refractive index of the optically-isotropic layer and the mean refractive index of the optically-anisotropic layer is at least 0.05. 
     
     
       5. The optical compensation film of  claim 1 , wherein the refractive index of the optically-isotropic layer has wavelength dispersion characteristics. 
     
     
       6. The optical compensation film of  claim 1 , wherein the refractive index of the optically-isotropic layer and the mean refractive index of the optically-anisotropic layer satisfy |n 1 (450)−n 2 (450)|≧0.05 in which n 1 (λ) and n 2 (λ) each mean the refractive index of the optically-isotropic layer and the mean refractive index of the optically-anisotropic layer, respectively, at a wavelength λ [nm]. 
     
     
       7. The optical compensation film of  claim 1 , wherein said at least one optically-isotropic layer is disposed on either of the surface or the rear surface thereof. 
     
     
       8. The optical compensation film of  claim 1 , wherein said at least one optically-isotropic layer is disposed on both the surface and the rear surface thereof. 
     
     
       9. A polarizing plate comprising a polarizing element and an optically compensation film as set forth in  claim 1 . 
     
     
       10. A liquid-crystal display device comprising an optical compensation film as set forth in  claim 1 .